JP2017091624A - Magnetic lead switch and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic lead switch which can improve operational reliability while reducing electric resistance at a contact portion, and also to provide a manufacturing method of the magnetic lead switch.SOLUTION: The magnetic lead switch according to the present invention comprises: a first conductive layer and a second conductive layer provided via a base insulation layer on a substrate; a first structure having a support part connected to the first conductive layer, a beam part whose one end is connected to the support part, and a movable electrode part connected to the other end of the beam part and movable with respect to the substrate; and a second structure which is connected to the second conductive layer and is arranged to face the movable electrode part of the first structure. On a surface of at least one of the first structure and the second structure, there is provided a contact metal layer containing a platinum group element.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a magnetic reed switch and a manufacturing method thereof.

Patent Document 1 and Patent Document 2 describe a mechanism device that functions as a magnetic reed switch.
In the mechanism device described in Patent Document 1, a lower electrode and an upper electrode are fixed on a substrate. The lower electrode is provided with the lower electrode magnetic material, the beam magnetic material is provided at the tip of the beam extending from the upper electrode, and the beam magnetic material is opposed to the upper electrode magnetic material with a gap therebetween. Yes. When an external magnetic field is applied, the beam portion magnetic material and the lower electrode magnetic material are magnetized and attracted to and contact each other, and a current flows between the lower electrode and the upper electrode. In the mechanism device, the upper electrode and the beam are made of gold.

  In the method of manufacturing a mechanical device described in Patent Document 1, a sacrificial layer is formed on a protective layer after a lower electrode magnetic material and a gold protective layer protecting the lower electrode magnetic material are formed on the substrate. Thereafter, an upper electrode layer is formed on the substrate, a beam continuous with the upper electrode layer is formed on the sacrificial layer, a beam magnetic material is formed on the tip of the beam, and then the sacrificial layer is formed. Remove.

  In the mechanism device described in Patent Document 2, a first copper foil and a second copper foil are provided on a substrate, a cantilever portion extends from the first copper foil, and the cantilever portion An upper electrode is provided at the tip. The cantilever portion is made of gold, and the upper electrode is made of a nickel layer that is a magnetic material and gold that covers the surface thereof. The lower electrode is formed by covering the second copper foil with gold, and the upper electrode and the lower electrode are vertically opposed to each other. In this mechanical device, when a magnetic field is generated from a magnet disposed below the substrate, the upper electrode is attracted to the magnetic field, the upper electrode comes into contact with the lower electrode, and a current flows between both electrodes.

  The mechanism device manufacturing method described in Patent Document 2 is substantially the same as that described in Patent Document 1, in which a sacrificial layer is formed on the second copper foil, and a cantilever portion and an upper electrode are formed thereon. After the formation, the sacrificial layer is removed.

JP 2004-335216 A JP 2008-276971 A

  In each of the mechanical devices described in Patent Document 1 and Patent Document 2, a magnetic material is provided on the upper electrode, and a beam portion that supports the magnetic material is formed of gold. However, since gold is a soft material and has extremely low rigidity, it is difficult to operably support an upper electrode having a magnetic material and having a relatively large mass. In particular, in both Patent Document 1 and Patent Document 2, the upper electrode moves up and down, and it is difficult to stably support the upper electrode moving up and down with a gold beam portion.

  Further, in the above structure device, when a switch that controls the contact and non-contact states by the operation of the upper electrode is configured, there is a problem of electrical resistance at the contact portion and a problem that the reliability of the operation cannot be sufficiently secured. Arise.

  SUMMARY OF THE INVENTION It is an object of the present invention to provide a magnetic reed switch capable of reducing the electrical resistance at the contact portion and improving the operation reliability and a method for manufacturing the same. Yes.

  In order to solve the above problems, a magnetic reed switch of the present invention includes a first conductive layer and a second conductive layer provided via a base insulating layer on a substrate, and a support unit connected to the first conductive layer, A first structure having a beam portion having one end connected to the support portion and a movable electrode portion connected to the other end of the beam portion and movable with respect to the substrate; and connected to the second conductive layer; And a contact metal layer containing a platinum group element is provided on at least one surface of the first structure and the second structure. It is characterized by that.

  According to such a configuration, since the contact metal layer containing a platinum group element is provided in the portion to be the contact in the first structure and the second structure, the electrical resistance at the contact is reduced and the reliability of the switch operation is increased. Improvements can be made.

  In the magnetic reed switch of the present invention, the contact metal layer may be provided on the entire exposed surface of at least one of the first structure and the second structure. Thereby, the bias of the stress in the part in which the contact metal layer is provided can be suppressed.

  In the magnetic reed switch of the present invention, the first structure and the second structure may contain a magnetic material. Thereby, the first structure and the second structure become magnetic induction layers, and contact and non-contact of the first structure and the second structure are controlled by the external magnetic field.

  In the magnetic reed switch of the present invention, the first reed switch is connected to the first conductive layer, is linearly arranged with respect to the second structure, and is arranged to face the movable electrode portion of the first structure, and includes a magnetic material. Three structures may be further provided. The third structure may be formed integrally with the first structure. Thereby, the switch by the state of contact and non-contact of the 2nd structure and the 3rd structure is constituted via the 1st structure.

  The method of manufacturing a magnetic reed switch according to the present invention includes a step of forming a first conductive layer and a second conductive layer via a first insulating layer on a substrate, and a step of forming a sacrificial layer on the first insulating layer. , A support part connected to the first conductive layer, one end connected to the support part, a beam part formed on the sacrificial layer, and connected to the other end of the beam part and formed on the sacrificial layer Forming a first structure having a movable electrode portion; and forming a second structure connected to the second conductive layer and disposed to face the movable electrode portion of the first structure; And a step of removing the sacrificial layer, and a step of forming a contact metal layer containing a platinum group element on at least one surface of the first structure and the second structure.

  According to such a configuration, a magnetic reed switch in which a contact metal layer containing a platinum group element is formed on at least one surface of the first structure and the second structure is manufactured.

  In the method for manufacturing a magnetic reed switch of the present invention, the contact metal layer may be formed by electrolytic plating. Thereby, the contact metal layer by electrolytic plating is formed on the required surface of the first structure and the second structure.

  In the method for manufacturing a magnetic reed switch of the present invention, the contact metal layer may be provided on the entire exposed surface of at least one of the first structure and the second structure. Thereby, the bias of the stress in the part in which the contact metal layer is provided can be suppressed.

  In the method for manufacturing a magnetic reed switch of the present invention, the first structure and the second structure may be formed by electrolytic plating using a magnetic material. As a result, the first structure and the second structure become magnetic induction layers, and a magnetic reed switch in which contact and non-contact of the first structure and the second structure are controlled by an external magnetic field is manufactured.

  In the method for manufacturing a magnetic reed switch according to the present invention, the step of forming the first conductive layer and the second conductive layer includes the step of forming a first pad electrode on the first conductive layer and a second pad electrode on the second conductive layer. Forming a common connection wiring at each of the end portions of the first conductive layer and the second conductive layer, and forming a second connection on the first pad electrode, the second pad electrode, and the common connection wiring. Forming a contact metal layer, and then removing a part of the second insulation layer by etching to expose the first pad electrode and the second pad electrode, and common connection wiring And a step of removing. Thereby, the first structure and the second structure can be formed by electrolytic plating through the common connection wiring.

  In the method for manufacturing a magnetic reed switch of the present invention, the step of exposing the first pad electrode and the second pad electrode and the step of removing the common connection wiring may be continuously performed by one etching. . Thus, after the first structure and the second structure are formed by electrolytic plating through the common connection wiring, the common connection wiring is removed, and individual magnetic leads using the first pad electrode and the second pad electrode are removed. The switch can be checked independently.

  In the method for manufacturing a magnetic reed switch of the present invention, the etching may be selective etching in which the second insulating layer and the common connection wiring are etched without etching the first conductive layer and the second conductive layer. Thus, the first pad electrode and the second pad electrode can be exposed and the common connection wiring can be removed by one etching.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to improve the rigidity of the beam part which supports a movable electrode part, and to provide the magnetic reed switch which can implement | achieve stable operation | movement, and its manufacturing method.

It is the perspective view which showed the outline | summary of the magnetic reed switch. (A) is a top view of a magnetic reed switch, (b) and (c) are sectional drawings of a magnetic reed switch. (A)-(f) is a schematic diagram explaining the manufacturing method of a magnetic reed switch. (A)-(f) is a schematic diagram explaining the manufacturing method of a magnetic reed switch. (A)-(f) is a schematic diagram explaining the manufacturing method of a magnetic reed switch. (A)-(f) is a schematic diagram explaining the manufacturing method of a magnetic reed switch. (A)-(d) is a schematic diagram explaining the manufacturing method of a magnetic reed switch. (A)-(d) is a schematic diagram explaining the manufacturing method of a magnetic reed switch. It is a top view explaining the manufacturing method of a magnetic reed switch.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same members are denoted by the same reference numerals, and the description of the members once described is omitted as appropriate.

(Configuration of magnetic reed switch)
FIG. 1 is a perspective view showing an outline of a magnetic reed switch.
2A is a plan view of the magnetic reed switch, and FIGS. 2B and 2C are cross-sectional views of the magnetic reed switch. 2B illustrates a cross-sectional view taken along line A1-A1 in FIG. 2A, and FIG. 2C illustrates a cross-sectional view taken along line A2-A2 in FIG.

  The magnetic reed switch 1 according to the present embodiment includes a first conductive layer 21 and a second conductive layer 22 provided via a base insulating layer 11 (first insulating layer) on the substrate 10, the first conductive layer 21, A first structure 30 that conducts, a second structure 40 that conducts to the second conductive layer 22, and a contact metal layer 80 are provided. In the present embodiment, a third structure 50, a first pad electrode 61, and a second pad electrode 62 are further provided.

The substrate 10 is a glass substrate or a glass epoxy substrate. As the substrate 10, a silicon (Si) substrate can be used. The base insulating layer 11 is formed on the first surface 10 a of the substrate 10. For the base insulating layer 11, silicon oxide (SiO ₂ ), silicon nitride (SiN), or the like is used. When the substrate 10 is a silicon substrate, a thermal oxide film may be used as the base insulating layer 11.

  The first conductive layer 21 and the second conductive layer 22 are provided apart from each other on the base insulating layer 11. For the first conductive layer 21 and the second conductive layer 22, for example, a NiFe alloy (nickel-iron alloy) is used. The first conductive layer 21 and the second conductive layer 22 are patterned into a predetermined shape.

  The first structure 30 is connected to the first conductive layer 21, is connected to the beam portion 32 having one end connected to the support portion 31, and the other end of the beam portion 32, and is movable with respect to the substrate 10. Movable electrode portion 33. That is, the first structure 30 is provided in a cantilever shape that floats from the beam portion 32 to the movable electrode portion 33. Accordingly, the movable electrode portion 33 can move on the substrate 10.

  The second structure 40 is connected to the second conductive layer 22 and disposed so as to face the movable electrode portion 33 of the first structure 30. That is, the first contact surface 33 a is provided on the second structure 40 side of the movable electrode portion 33, and the second contact surface 40 a is provided on the movable electrode portion 33 side of the second structure 40. A slight gap is provided between the first contact surface 33a and the second contact surface 40a.

  The third structure 50 is connected to the first conductive layer 21, is disposed linearly with respect to the second structure 40, and is disposed so as to face the movable electrode portion 33 of the first structure 30. . A third contact surface 50 a is provided on the movable electrode portion 33 side of the third structure 50. A slight gap is provided between the first contact surface 33a and the third contact surface 50a. The third structure 50 may be formed integrally with the first structure 30.

  The first pad electrode 61 is electrically connected to the first conductive layer 21, and the second pad electrode 62 is electrically connected to the second conductive layer 22. The first pad electrode 61 and the second pad electrode 62 are exposed from the base insulating layer 11.

  In the magnetic reed switch 1 of this embodiment, when the movable electrode portion 33 moves on the substrate 10, the first contact surface 33a and the second contact surface 40a are in contact / non-contact state, and the first contact surface 33a and the first contact surface 33a. The contact / non-contact state with the 3-contact surface 50a changes. For example, when the movable electrode portion 33 moves toward the second structure body 40 and the third structure body 50, the first contact surface 33a contacts the second contact surface 40a and the third contact surface 50a, and moves to the opposite side. By (or returning to the original position), the first contact surface 33a, the second contact surface 40a, and the third contact surface 50a are brought into a non-contact state.

  Each of the first structure 30, the second structure 40, and the third structure 50 includes a magnetic material. For example, a NiFe alloy is used as the magnetic material. The magnetic material can be selected from various soft magnetic materials such as a CoFe alloy (cobalt-iron alloy) and a CoNiFe alloy (cobalt-nickel-iron alloy).

  In the magnetic reed switch 1, a contact metal layer 80 is provided on at least one surface of the first structure 30 and the second structure 40. In the magnetic reed switch 1 according to the present embodiment, a contact metal layer 80 is provided on each surface of the first structure 30 and the second structure 40. Furthermore, a contact metal layer 80 is also provided on the surface of the third structure 50.

  When a magnetic material such as a NiFe alloy contained in the first structure 30 and the second structure 40 is exposed to the atmosphere, a natural oxide film is easily formed on the surface. For this reason, there is a possibility that stable electrical contact may not be obtained between the first contact surface 33a and the second contact surface 40a. Therefore, by providing the contact metal layer 80 on at least one surface of the first structure 30 and the second structure 40, formation of a natural oxide film is suppressed, and the movable electrode portion 33 and the second structure 40 Low electrical resistance at the contact is achieved.

  The contact metal layer 80 includes a platinum group element. Examples of the platinum group element used for the contact metal layer 80 include ruthenium (Ru), rhodium (Rh), iridium (Ir), and palladium (Pd). By forming a platinum group that is difficult to oxidize and has high mechanical strength as the contact metal layer 80, conduction at the contact can be stabilized.

  The contact metal layer 80 is formed on the surface of the first structure 30 containing a magnetic material by electrolytic plating or sputtering. When the platinum group is formed by electrolytic plating, an underlayer such as gold (Au) may be formed between the magnetic material and the contact metal layer 80 as a buffer layer that relieves the stress.

  The contact metal layer 80 is preferably provided on the entire exposed surface of at least one of the first structure 30 and the second structure 40. By covering the entire exposed surface with the contact metal layer 80, it is possible to suppress the uneven stress in the portion where the contact metal layer 80 is provided. That is. By providing the contact metal layer 80 containing such a platinum group element, it is possible to reduce the electrical resistance at the contact and improve the reliability of the switch operation.

Next, the operation of the magnetic reed switch 1 will be described.
This magnetic reed switch 1 is sensitive to an external magnetic field in the Y1 direction. As shown in FIG. 1, the external magnetic field B directed in the Y1 direction is attracted to the support portion 31 of the first structure 30 containing the magnetic material, and the magnetic flux Φ passes through the inside of the magnetic material, so that the third structure 50 is led to the second structure 40 through the movable electrode portion 33.

  The third structure 50 is elongated in the Y direction on the Y2 side with respect to the facing range W1 between the second structure 40 and the movable electrode portion 33. Further, the third structure 50 is opposed to the movable electrode portion 33. It extends longer in the Y2 direction than the range W2. By forming the third structure 50 and the second structure 40 to be elongated in the Y direction, the Y direction becomes the easy axis due to the magnetic anisotropy of the magnetic material.

  Therefore, the third structure 50 serves as a magnetic induction layer, and the magnetic flux Φ attracted to the support portion 31 of the first structure 30 passes through the third structure 50 and the second structure 40 and the movable electrode portion 33. Is effectively guided to a facing range W1. The function as the magnetic induction layer can be exhibited for both the external magnetic field B oriented in the Y1 direction and the external magnetic field B oriented in the Y2 direction.

  When the magnetic flux Φ passes through the magnetic materials facing each other in the movable electrode portion 33 and the second structure 40, the opposite portions of the magnetic material of the movable electrode portion 33 and the magnetic material of the second structure 40 are reversed. Magnetic poles. Thereby, the magnetic attractive force F toward the second structure 40 acts on the movable electrode portion 33.

  Further, at the facing portion between the movable electrode portion 33 and the third structure 50, each magnetic material has a reverse magnetic polarity, so that an attractive force is exerted and the movable electrode portion 33 is directed toward the second structure 40. The magnetic attractive force F is increased. This magnetic attraction force F increases as the density of the magnetic flux Φ passing through the opposing magnetic material increases. Due to the magnetic attractive force F thus increased, the beam portion 32 is elastically bent, and the movable electrode portion 33 is in contact with the second structure 40.

  A first conductive layer 21 and a second conductive layer 22 are provided on the substrate 10 with the base insulating layer 11 interposed therebetween. The first structure 30 and the third structure 50 are electrically connected to the first conductive layer 21, and the second structure 40 is electrically connected to the second conductive layer 22. When the movable electrode portion 33 and the second structure 40 come into contact with each other, a current flows between the first conductive layer 21 and the second conductive layer 22, and the switch is turned on.

  Note that the minimum value of the facing distance between the third structure 50 and the movable electrode portion 33 is preferably smaller than the minimum value of the facing distance between the second structure 40 and the third structure 50. Similarly, it is preferable that the minimum value of the facing distance between the second structure 40 and the movable electrode portion 33 is smaller than the minimum value of the facing distance between the second structure 40 and the third structure 50. Accordingly, the magnetic flux Φ passing through the third structure 50 is more easily guided to the movable electrode portion 33 than the second structure 40, and the magnetic flux Φ is likely to contribute to the magnetic attractive force F. This is the same when the magnetic flux Φ directed in the Y2 direction is directed from the second structure 40 to the movable electrode portion 33.

  In this magnetic reed switch 1, since the magnetic material forming the third structure 50 functions as a magnetic derivative, the external magnetic field B directed in the Y1 direction is attracted to the support portion 31 and further to the third structure 50. As a result, the magnetic material constituting the movable electrode portion 33 and the magnetic material constituting the second structure 40 are effectively provided. Therefore, the density of the magnetic flux Φ applied to the movable electrode portion 33 and the second structure 40 can be increased, and the operation can be performed even if the external magnetic field B is relatively small, and the operation sensitivity can be increased.

  In addition, since the movable electrode portion 33 faces both the second structure body 40 and the third structure body 50, the movable electrode portion 33 is operated by both the second structure body 40 and the third structure body 50. Magnetic attraction force F is exhibited. Accordingly, the operation speed is increased and the operation response is improved.

  In the magnetic reed switch 1, the second structure 40 is elongated to the Y1 side from the facing range W1 to the movable electrode portion 33, and the magnetic material forming the second structure 40 also functions as a magnetic induction layer. ing. Therefore, the magnetic field directed in the Y2 direction is also attracted to the second structure 40, passes through the second structure 40 formed elongated in the Y direction, and is effectively guided to the movable electrode portion 33. Accordingly, it is possible to operate with high sensitivity even with respect to the magnetic field directed in the Y2 direction.

(Manufacturing method of magnetic reed switch)
Next, a method for manufacturing the magnetic reed switch 1 will be described.
FIG. 3A to FIG. 9 are schematic views illustrating a method for manufacturing a magnetic reed switch.
3A to 3C are cross-sectional views, and FIGS. 3D to 3F are plan views corresponding to FIGS. 3A to 3C, respectively.
4A to 4C are cross-sectional views, and FIGS. 4D to 4F are plan views corresponding to FIGS. 4A to 4C, respectively.
5A to 5C are cross-sectional views, and FIGS. 5D to 5F are plan views corresponding to FIGS. 5A to 5C, respectively.
6A to 6C are cross-sectional views, and FIGS. 6D to 6F are plan views corresponding to FIGS. 6A to 6C, respectively.
7A and 7B are cross-sectional views, and FIGS. 7C and 7D are plan views corresponding to FIGS. 7A and 7B, respectively.
8A and 8B are cross-sectional views, and FIGS. 8C and 8D are plan views corresponding to FIGS. 8A and 8B, respectively.
FIG. 9 is a plan view of the entire substrate.
Note that the cross-sectional views in FIGS. 3 to 8 represent cross sections taken along the alternate long and short dash line CL shown in the corresponding plan views.

  First, as shown in FIGS. 3A and 3D, the base insulating layer 11 is formed on the surface of the substrate 10. In the present embodiment, a Si substrate is used as the substrate 10. In this case, the base insulating layer 11 made of a thermal oxide film is formed by heat treating the Si substrate.

  Next, as shown in FIGS. 3B and 3E, the conductive material layer 20 is formed on the base insulating layer 11, and the first pad electrode 61 and the second pad electrode are further formed on the conductive material layer 20. 62 is formed. For example, a NiFe alloy is used for the conductive material layer 20 and is formed by sputtering or the like. For example, Au is used for the first pad electrode 61 and the second pad electrode 62. The first pad electrode 61 and the second pad electrode 62 are patterned by photolithography and etching.

  Next, as shown in FIGS. 3C and 3F, the conductive material layer 20 is patterned to form the first conductive layer 21 and the second conductive layer 22. In this patterning, as shown in FIG. 9, the conductive material layer 20 is left along the dicing line DL of the substrate 10, and the common electrode 25 used in the subsequent plating process is formed.

Next, as shown in FIGS. 4A and 4D, a first protective insulating layer 12 is formed on the entire surface. For example, SiN _x is used for the first protective insulating layer 12. The thickness of the first protective insulating layer 12 is, for example, about 300 nm (nanometers) or more and 500 nm or less. Thus, the first protective insulating layer 12 is formed on the base insulating layer 11, the first conductive layer 21 and the second conductive layer 22, and the first pad electrode 61 and the second pad electrode 62.

  Next, as shown in FIGS. 4B and 4E, a part of the first protective insulating layer 12 is removed, an opening is formed, and the first pad electrode 61 and the second pad electrode 62 are exposed. Further, the respective end portions of the first conductive layer 21 and the second conductive layer 22 and a part of the first protective insulating layer 12 on the outside thereof are also removed. Thereby, each edge part of the 1st conductive layer 21 and the 2nd conductive layer 22 is also exposed.

  Next, as shown in FIGS. 4C and 4F, the common connection wiring 23 is formed so as to be electrically connected to the end portions of the first conductive layer 21 and the second conductive layer 22 exposed in the previous step. To do. For the common connection wiring 23, a material such as tantalum (Ta) or titanium (Ti) that is selectively etched in a later process is used.

  The common connection wiring 23 is formed by lift-off, for example. The common connection wiring 23 is formed so as to straddle the dicing line DL. As a result, the first conductive layer 21 and the second conductive layer 22 in the adjacent element region are brought into conduction via the common connection wiring 23. Further, the second conductive layer 22 and the first conductive layer 21 in the adjacent element region are brought into conduction through the common connection wiring 23.

  Since the common electrode 25 is formed on the dicing line DL, the first conductive layer 21 and the second conductive layer 22 in each element region on the substrate 10 are all conductive through the common electrode 25 and the common connection wiring 23. It becomes a state.

Next, as shown in FIGS. 5A and 5D, a second protective insulating layer 13 (second insulating layer) is formed on the entire surface. For example, SiN _x is used for the second protective insulating layer 13. The thickness of the second protective insulating layer 13 is, for example, about 300 nm to 500 nm. Thereby, the second protective insulating layer 13 is formed on the first protective insulating layer 12, on the first pad electrode 61 and the second pad electrode 62, and on the common connection wiring 23.

  In addition, when the 2nd protective insulating layer 13 of the same material is laminated | stacked on the 1st protective insulating layer 12, these are united. Therefore, the thickness of the insulating layer in the portion where only the second protective insulating layer 13 is formed (on the first pad electrode 61, on the second pad electrode 62, and on the common connection wiring 23) is the first protection. The insulating layer 12 and the second protective insulating layer 13 are thinner than the insulating layer where the insulating layer 12 and the second protective insulating layer 13 are stacked.

  Next, as shown in FIGS. 5B and 5E, a part of the second protective insulating layer 13 on the first conductive layer 21 and the second conductive layer 22 is removed and opened. This opening becomes a contact hole of the first conductive layer 21 and the second conductive layer 22.

  Next, as shown in FIGS. 5C and 5F, an insulating layer (the base insulating layer 11, the first protective insulating layer 12 and the second protective layer) between the first conductive layer 21 and the second conductive layer 22 is used. A sacrificial layer 15 is formed on a portion where the insulating layer 13 is stacked. For example, a resist is used for the sacrificial layer 15.

  Next, as shown in FIGS. 6A and 6D, a seed layer 24 is formed on the entire surface. The seed layer 24 is a layer that becomes a plating base in a subsequent plating step. For example, Cu is used for the seed layer 24.

  Next, as shown in FIGS. 6B and 6E, part of the seed layer 24 is removed, and part of the first conductive layer 21 and the second conductive layer 22 is exposed. The seed layer 24 is removed by, for example, ion milling.

  Next, as shown in FIGS. 6C and 6F, the first structure 30, the second structure 40, and the third structure 50 are formed by electrolytic plating. Here, a resist is formed in a region other than the region where the first structure 30, the second structure 40, and the third structure 50 are formed, and electrolytic plating is performed using the seed layer 24 as a base. For electrolytic plating, a magnetic material such as a NiFe alloy is deposited. After the first structure 30, the second structure 40, and the third structure 50 are formed, the resist is removed.

  In the present embodiment, the first conductive layer 21 and the second conductive layer 22 in each element region on the substrate 10 are all in a conductive state via the common electrode 25 and the common connection wiring 23. Therefore, for example, when the common electrode 25 is energized, the first structure 30, the second structure 40, and the third structure 50 including the magnetic material can be deposited by electrolytic plating in all element regions.

  Next, as shown in FIGS. 7A and 7C, the seed layer 24 is etched. When Cu is used as the seed layer 24, the seed layer 24 is removed by wet etching using, for example, copper chloride.

  Next, as shown in FIGS. 7B and 7D, the sacrificial layer 15 is removed. When a resist is used as the sacrificial layer 15, the sacrificial layer 15 that is a resist is removed by a release agent. When the sacrificial layer 15 is removed, spaces are formed between the beam portion 32 and the movable electrode portion 33 of the first structure 30 and the substrate 10 to form a cantilever shape.

  Next, as shown in FIGS. 8A and 8C, the contact metal layer 80 is formed on the exposed surfaces of the first structure 30, the second structure 40, and the third structure 50. For the contact metal layer 80, a platinum group element (for example, Ru, Rh, Ir, Pd) is used. The contact metal layer 80 is formed by electrolytic plating. In addition, you may form Au by plating etc. as a foundation | substrate of this electrolytic plating.

  In the present embodiment, the first structure 30, the second structure 40, and the third structure 50 in each element region on the substrate 10 are the first conductive layer 21, the second conductive layer 22, the common connection wiring 23, and the common. All are conductive through the electrode 25. Therefore, for example, when the common electrode 25 is energized, the platinum group contact metal layer 80 is deposited on the surfaces of the first structure 30, the second structure 40, and the third structure 50 by electrolytic plating in all element regions. be able to.

  Next, as shown in FIGS. 8B and 8D, a part of the second protective insulating layer 13 is removed. Here, for example, selective etching by RIE (Reactive Ion Etching) is performed. By this etching, the second protective insulating layer 13 under the beam portion 32 and the movable electrode portion 33 of the first structure 30 remains, but the other portions are removed.

  When the second protective insulating layer 13 is removed, the first pad electrode 61 and the second pad electrode 62, the respective end portions of the first conductive layer 21 and the second conductive layer 22, and the common connection wiring 23 are exposed. When the etching is further advanced, the common connection wiring 23 is removed. In this etching, the etching rate of the material of the common connection wiring 23 is higher than the material of the first conductive layer 21 and the second conductive layer 22. Therefore, the respective ends of the first conductive layer 21 and the second conductive layer 22 remain, and the common connection wiring 23 is removed.

  When the common connection wiring 23 is removed. The first conductive layer 21 and the second conductive layer 22 in each element region on the substrate 10 are separated from the common electrode 25. When the common connection wiring 23 is removed, a plurality of magnetic reed switches 1 are formed on one substrate 10 in an electrically independent state. In this step, the first pad electrode 61 and the second pad electrode 62 are exposed and the common connection wiring 23 is removed by a single etching process, but the second protective insulating layer is separately processed. 13, the first pad electrode 61 and the second pad electrode 62 may be exposed, and the common connection wiring 23 may be removed.

  Next, an operation inspection of each magnetic reed switch 1 is performed using the first pad electrode 61 and the second pad electrode 62 in each element region. In the present embodiment, the operation of each magnetic reed switch 1 on the substrate 10 can be inspected without cutting the substrate 10 along the dicing line DL and dividing the substrate 10 into individual magnetic reed switches 1.

  After the operation of the magnetic reed switch 1 is inspected, the substrate 10 is cut along the dicing line DL and divided into individual magnetic reed switches 1.

  Thus, in the manufacturing method of the magnetic reed switch 1 according to the present embodiment, when the contact metal layer 80 is formed on the surface of the first structure 30, the second structure 40, and the third structure 50 by plating, There is no need to use a resist to cover the parts that do not require plating.

  Further, after the contact metal layer 80 is formed by plating, the common connection wiring 23 can be removed by etching together with the exposure of the first pad electrode 61 and the second pad electrode 62. Thereby, each magnetic reed switch 1 on the board | substrate 10 can be electrically independent, and it becomes possible to test | inspect the operation | movement of each magnetic reed switch 1 before the dicing of the board | substrate 10. FIG.

  Therefore, before the substrate 10 is diced, variation in the characteristics of the magnetic reed switch 1 within the substrate 10 can be grasped and used as data for improving the characteristics. Further, quality control such as defect elimination after division into individual magnetic reed switches 1 can be easily performed.

  In addition, although this embodiment and its specific example were demonstrated above, this invention is not limited to these examples. For example, in the present embodiment, an example in which the movable electrode portion 33 is movable in the X direction has been shown, but a magnetic reed switch that is movable in a direction orthogonal to the first surface 10a of the substrate 10 may be used. Further, those in which those skilled in the art appropriately added, deleted, and changed the design of the above-described embodiments or specific examples thereof, and combinations of the features of each embodiment as appropriate are also included in the present invention. As long as the gist is provided, it is included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Magnetic reed switch 10 ... Board | substrate 10a ... 1st surface 11 ... Base insulating layer 12 ... 1st protective insulating layer 13 ... 2nd protective insulating layer 15 ... Sacrificial layer 20 ... Conductive material layer 21 ... 1st conductive layer 22 ... 1st 2 conductive layer 23 ... common connection wiring 24 ... seed layer 25 ... common electrode 30 ... first structure 31 ... support part 32 ... beam part 33 ... movable electrode part 33a ... first contact surface 40 ... second structure 40a ... second 2 contact surface 50 ... 3rd structure 50a ... 3rd contact surface 61 ... 1st pad electrode 62 ... 2nd pad electrode 80 ... contact metal layer B ... external magnetic field DL ... dicing line F ... magnetic attraction force W1 ... opposing range W2 ... opposing range Φ ... magnetic flux

Claims (12)

A first conductive layer and a second conductive layer provided via an insulating layer on the substrate;
A support unit connected to the first conductive layer; a beam unit having one end connected to the support unit; and a movable electrode unit connected to the other end of the beam unit and movable with respect to the substrate. A structure,
A second structure connected to the second conductive layer and disposed to face the movable electrode portion of the first structure;
With
A magnetic reed switch characterized in that a contact metal layer containing a platinum group element is provided on at least one surface of the first structure and the second structure.   The magnetic reed switch according to claim 1, wherein the contact metal layer is provided on the entire exposed surface of at least one of the first structure and the second structure.   The magnetic reed switch according to claim 1 or 2, wherein the first structure and the second structure include a magnetic material.   A third structure that is connected to the first conductive layer, is arranged linearly with respect to the second structure, and is arranged to face the movable electrode portion of the first structure, and includes a magnetic material; The magnetic reed switch according to claim 1, further comprising:   The magnetic reed switch according to claim 4, wherein the third structure is formed integrally with the first structure. Forming a first conductive layer and a second conductive layer via a first insulating layer on the substrate;
Forming a sacrificial layer on the first insulating layer;
A support part connected to the first conductive layer, one end connected to the support part, a beam part formed on the sacrificial layer, and connected to the other end of the beam part, on the sacrificial layer Forming a first structure having a movable electrode portion to be formed;
Forming a second structure that is connected to the second conductive layer and disposed to face the movable electrode portion of the first structure;
Removing the sacrificial layer;
Forming a contact metal layer containing a platinum group element on at least one surface of the first structure and the second structure;
A method of manufacturing a magnetic reed switch, comprising:   The method of manufacturing a magnetic reed switch according to claim 6, wherein the contact metal layer is formed by electrolytic plating.   The method of manufacturing a magnetic reed switch according to claim 6, wherein the contact metal layer is provided on the entire exposed surface of at least one of the first structure and the second structure.   The method of manufacturing a magnetic reed switch according to any one of claims 6 to 8, wherein the first structure and the second structure are formed by electrolytic plating using a magnetic material. The step of forming the first conductive layer and the second conductive layer includes:
Forming a first pad electrode on the first conductive layer and a second pad electrode on the second conductive layer;
Forming a common connection wiring at each of an end portion of the first conductive layer and an end portion of the second conductive layer;
Forming a second insulating layer on the first pad electrode, the second pad electrode and the common connection wiring,
After forming the contact metal layer, removing a part of the second insulating layer by etching to expose the first pad electrode and the second pad electrode;
The method for manufacturing a magnetic reed switch according to claim 6, further comprising a step of removing the common connection wiring.   The method for manufacturing a magnetic reed switch according to claim 10, wherein the step of exposing the first pad electrode and the second pad electrode and the step of removing the common connection wiring are successively performed by the etching. The method of manufacturing a magnetic reed switch according to claim 11, wherein the etching is selective etching in which the second insulating layer and the common connection wiring are etched without etching the first conductive layer and the second conductive layer.

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